1. Field of the Invention
The invention is related to an improvement for ski boots. More particularly, the present invention is related to a ski boot having a shell base adapted to surround the foot, and an upper portion adapted to envelope the lower part of the leg of the skier, capable of comprising at least one integral piece. This upper portion is, furthermore, journalled on the shell base and is capable of pivoting towards the rear by virtue of the unlatching of an abutment system, that enables the boot to be more easily put on, as well as a so-called resting position, without it being necessary to modify the initial tightening of the upper on the lower part of the leg when the boot according to the invention is put on by the skier. Advantageously, these functions of the boot according to the invention are obtained by manipulating a single element controlling the unlatching of the abutment system, thereby achieving a rotational release about an axis substantially in the area of the axis of the malleoli of the leg of the skier with respect to the shell base.
2. Description of Background and Material Information
Prior state of the art includes a certain number of ski boots whose structures were aimed at achieving the same results of releasing the upper with respect to the shell base. However, the structures described neither comprise the same means nor the same functions as those of the boot according to the invention.
Thus, the boot according to the European Patent Application EP 286,586 includes a construction enabling the skier who wishes to relax or walk, to unlatch one of the rear portions constituting the upper of the boot with respect to the shell by pressing on a rocking lever connected to a spring, thereby enabling him to bring the leg back into a more or less vertical position, and enabling the upper assembly thus released to pivot about its journal on the shell base.
Although the function of releasing the upper with respect to the shell base is, in fact, achieved in this instance, it is done at the cost of a relatively complex and expensive boot structure described therein. Indeed, in this case, one is faced with a plurality of upper portions assembled pivotally with respect to one another, which, when called upon to respond to the anatomical necessities of the articulations of the feet, generate interdependent movements between themselves, adversely affecting precision skiing.
The manufacturer realized the disadvantages of these boots after having commercialized them, and tried to overcome these by offering the consumers a boot which was conceived according to a second embodiment of the invention, and commercialized under the name "MID 4-8".
With this new boot, the objects of structural simplicity and cost reduction were apparently resolved, but this was done at the detriment of the release function of the angle of advance of the upper with respect to the shell base, which suffered substantially. In fact, what one finds here is a boot of the front entry type, as described, for example, in Swiss Patent CH 549,970.
In another embodiment described in International Patent Application WO 89/04615, a boot of the central entry type is disclosed whose upper, comprising three distinct portions, all journalled with respect to the shell base, comprises a blocking-unblocking mechanism for its position of advance. This mechanism, although it permits movement from a skiing position to a walking position of the boot closed on the foot of the skier, it does not, however, enable good foot retention, especially in the area of the flexion fold.